Traditionally, a horseback riding stirrup is composed of a loop, two branches, and a bottom.
The use of two branches allows the rider to more easily remain in the stirrups, since the foot is only able to exit through a rearward motion, and it is not possible to lose the stirrup through a lateral movement. The drawback of using two branches is the danger of a foot becoming blocked in the stirrup if it is inserted too far. The use of a heeled boot arises from the need to protect the rider from that risk of becoming blocked. It is effective without being perfect or helping the rider to remain in the stirrups in all situations.